Project Carbon Longtail

2008 BMW 328i E90

R261

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6 photos

Media Studies

6 images

Comparison Study I ↗

Comparison Study II ↗

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Story

Project Carbon Longtail takes the E90 328i—one of BMW’s most familiar silhouettes—and drags it into the endurance-prototype rulebook without losing the sedan’s DNA. The greenhouse, four-door proportions, and window lines stay readable, but everything below the beltline becomes aero-first: a forward-thrown wedge nose, near-closed front wheelhouses, and a tail stretched long for stability at speed.

This isn’t a cartoon widebody. It’s a believable “works skunkworks” exercise built around airflow control, thermal management, and track width—front +190mm, rear +230mm—so the stance supports the aero rather than just the look. Carbon surfaces, ducting, and a longtail deck turn the E90 into something that reads Group C from 50 meters, yet still feels engineered from the platform up.

Blueprint

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Collectible Poster

Collector's Edition

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Technical dossier

Fictional engineering concept

Platform

2008 BMW 328i E90

Powertrain concept

N52 3.0L inline-six retained but shifted ~75mm rearward for near front-mid mass distribution
Sidepod-style cooling with ducted inlets and defined extraction through fender/roof outlets for sustained heat load
Motorsport brake cooling plenum fed by high-pressure nose intake and wheelhouse ducting
Exhaust routed to a central quad-exit integrated within the diffuser with heat-shielded carbon surrounds

Aero package

Near-covered front wheelhouses with vertical outer lips to manage wheel wake and reduce turbulence
Dual dive planes per side and flat underbody shelf-style skirts with a concave acceleration channel
Seven-channel deep rear diffuser with defined venturi tunnels and controlled blunt trailing edges
Tri-element swan-neck rear wing with adjustable flap and full-width Gurney for endurance stability

Chassis & stance

2008 BMW 328i E90

Wheels & tires

OZ Racing Chrono forged magnesium: 19x9.5 front
19x11.5 rear
Michelin Pilot Sport Cup 2 slick-spec: 315/30-19 front
345/30-19 rear
Ride height target: ~35mm front / ~40mm rear ground clearance with hydraulic bumpstops
Wheelhouse packaging designed around 90% front coverage and full rear enclosure for aero cleanliness

Fabrication notes

Carbon/FRP hybrid outer skins over a reinforced substructure to support long overhangs and aero loads
Wheelhouse covers built as serviceable panels with quick-release fasteners for tire and brake access
Diffuser and wing mounts tied into chassis hardpoints with load paths designed for sustained downforce
Ducting treated as a system: sealed inlets
smooth radii
and controlled exits to prevent pressure bleed